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assembly of life sciences (u.s.). committee on aldehydes
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Documents and information from the NASA Network Resource and Training Site.
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Topic: nasa
Books to Borrow
by Assembly of Life Sciences (U.S.). Committee on Aldehydes
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Includes bibliographical references
Topics: Formaldehyde, Aldehydes
Universal Library
by National Research Council
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Topic: Health
JSTOR Early Journal Content, The American Naturalist
by P.
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"Formaldehyde" is an article from The American Naturalist, Volume 34 . View more articles from The American Naturalist . View this article on JSTOR . View this article's JSTOR metadata . You may also retrieve all of this items metadata in JSON at the following URL: https://archive.org/metadata/jstor-2454467
Source: http://www.jstor.org/stable/10.2307/2454467
Books to Borrow
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Rev. German ed. published in 1971 under title: Einführung in die Molekülspektroskopie
Topics: Molecular spectroscopy, Radicals (Chemistry), Ions, Molecular structure, Spectre, Radicaux...
Folkscanomy Science: Books of a Scientific Nature
by Gordon M. Barrow
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Gordon M. Barrow Introduction to Molecular Spectroscopy McGraw-Hill 1962 Acrobat 7 Pdf 12.9 Mb. Scanned by artmisa using Canon DR2580C + flatbed option
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Topics: Chemistry, Physics, Diatomic, Polyatomic, Rotation, Vibration, Bohr, Quantum
This was the fourth in a series of colloquia begun at the University of Lund, Sweden in 1983 and subsequently held in Toledo, Ohio and Amsterdam, The Netherlands. The purpose of these meetings is to provide an international forum for communication between major users of atomic spectroscopic data and the providers of these data. These data include atomic wavelengths, line shapes, energy levels, lifetimes, and oscillator strengths. Speakers were selected from a wide variety of disciplines...
Topics: NASA Technical Reports Server (NTRS), ASTROPHYSICS, ATOMIC SPECTRA, ENERGY LEVELS, OSCILLATOR...
Books to Borrow
by Drake, Gordon W. F
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Includes bibliographical references and index
Topics: Atoms, Physics, Molecules, Optics
NIST Monograph
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NIST Monograph
Universal Library
by Herzberg,Gerhard.
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Topics: NATURAL SCIENCES, Physics, Mechanics of gases. Aeromechanics. Plasma physics
Includes bibliographical references (pages xvii-xviii)
Topic: Spectrum analysis
NASA Network Resource and Training Site
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The availability of space science data, a description of the data, and a description of the services supplied by the National Space Science Data Center (NSSDC) is presented. A series of cumulative indexes that reference the data descriptions contain: (1) a chronological listing of all spacecraft, experiments, and data descriptions; (2) an index of all spacecraft described, identified by common names and alternate names; (3) a listing of the original experiment institutions for experiments...
Topics: NASA Technical Reports Server (NTRS), AEROSPACE SCIENCES, CATALOGS (PUBLICATIONS), INDEXES...
NASA Network Resource and Training Site
by NASA Technical Reports Server (NTRS)
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Solar physics was reviewed in the context of the solar atmoshere. The understanding of the solar atmosphere is linked to stellar atmospheric research. Topics covered include: the existence of the chromosphere, the corona, and the solar wind; the interactive complex of convection, differential rotation, magnetic field generation and concentration, and the activity cycle; phenomena such as granulation, supergranulation, the 5 minute oscillation, filigree, faculae, sunspots, spicules, prominences,...
Topics: NASA Technical Reports Server (NTRS), SOLAR ACTIVITY, SOLAR ATMOSPHERE, SOLAR MAGNETIC FIELD, SOLAR...
Physical insights into the various astronomical objects which were studied using the International Ultraviolet Explorer (IUE) satellite. Topics covered included galaxies, cool stars, hot stars, close binaries, variable stars, the interstellar medium, the solar system, and IUE follow-on missions.
Topics: NASA Technical Reports Server (NTRS), GALAXIES, INTERSTELLAR MATTER, IUE, NEBULAE, SOLAR SYSTEM,...
Solar chromospheric models are described. The models included are based on the observed spectrum, and on the assumption of hydrostatic equilibrium. The calculations depend on realistic solutions of the radiative transfer and statistical equilibrium equations for optically thick lines and continua, and on including the effects of large numbers of lines throughout the spectrum. Although spectroheliograms show that the structure of the chromosphere is highly complex, one-dimensional models of...
Topics: NASA Technical Reports Server (NTRS), CHROMOSPHERE, MATHEMATICAL MODELS, SOLAR ATMOSPHERE,...
Highlights of the results obtained from the IUE satellite are addressed. specific topics discussed include the solar system, O-A stars, F-M stars, binary stars and highly evolved objects, nebulae and interstellar medium, and extragalactic objects. Data reduction techniques employed in the analysis of the varied data are also discussed.
Topics: NASA Technical Reports Server (NTRS), CONFERENCES, IUE, SPACEBORNE ASTRONOMY, ULTRAVIOLET...
Optical measurements of trace species in the atmosphere require precise, accurate spectroscopic data for the molecules under study. This laboratory exits to provide high quality spectroscopic data for the interpretation of data from existing satellite, balloon, ground, and aircraft instruments, as well as to provide sufficient data to assess the feasibility of new instruments.
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC COMPOSITION, HYDROXYL RADICALS, MOLECULAR...
NASA Network Resource and Training Site
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The Ion Beam Experiment at the Center for Astrophysics is dedicated to the study of ion-electron collision processes of importance in solar physics. The analysis of measurements of Electron Impact Excitation (EIE) from the 3s3p(exp 3)P(exp o) metastable state to the 3s3p(exp 1)P state of Si(2+) was completed during the past year and a paper describing the results is available as a preprint. Our current program is directed at measuring absolute cross sections for dielectronic recombination (DR)...
Topics: NASA Technical Reports Server (NTRS), ATOMIC EXCITATIONS, ELECTRON IMPACT, ELECTRON-ION...
The processes and parameters in atomic and molecular physics that are relevant to solar physics are investigated. The areas covered include: (1) measurement of atomic and molecular parameters that contribute to discrete and continous sources of opacity and abundance determinations in the sun; (2) line broadening and scattering phenomena; and (3) development of an ion beam spectroscopic source which is used for the measurement of electron excitation cross sections of transition region and...
Topics: NASA Technical Reports Server (NTRS), SOLAR ACTIVITY, SOLAR PHYSICS, ULTRAVIOLET RADIATION,...
Progress is given on work on: cross section measurements in the transmission window regions of the Schumann-Runge bands of oxygen; the determinations of predissociation linewidths; the theoretical calculation of band oscillator strengths of the Schumann-Runge absorption bands of O-16O-18; the determination of molecular spectroscopic constants; and the combined Herzberg continuum cross sections. The experimental investigations relevant to the cross section measurements, predissociation...
Topics: NASA Technical Reports Server (NTRS), ABSORPTION CROSS SECTIONS, ATMOSPHERIC COMPOSITION, COMPUTER...
An account is given of progress during the period 8/l/96-7/31/97 on work on (a) cross section measurements of O2 S-R using a Fourier transform spectrometer (FTS) at the Photon Factory in Japan; (b) the determination of the predissociation linewidths of the Schumann-Runge bands (S-R) of 02; (c) cross section measurements of 02 Herzberg bands using a Fourier transform spectrometer (FTS) at Imperial College; and (d) cross section measurements of H2O in the wavelength region 120-188 nm. The...
Topics: NASA Technical Reports Server (NTRS), OXYGEN ATOMS, FOURIER TRANSFORMATION, PHOTOCHEMICAL...
American Libraries
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The American Libraries collection includes material contributed from across the United States. Institutions range from the Library of Congress to many local public libraries. As a whole, this collection of material brings holdings that cover many facets of American life and scholarship into the public domain. Significant portions of this collection have been generously sponsored by Microsoft , Yahoo! , The Sloan Foundation , and others.
This volume contains the final report for the International Ultraviolet Explorer IUE Observatory Operations contract. The fundamental operational objective of the International Ultraviolet Explorer (IUE) program is to translate competitively selected observing programs into IUE observations, to reduce these observations into meaningful scientific data, and then to present these data to the Guest Observer in a form amenable to the pursuit of scientific research. The IUE Observatory is the key to...
Topics: NASA Technical Reports Server (NTRS), CALIBRATING, DATA PROCESSING, IMAGE PROCESSING, IUE, SOFTWARE...
The scientific instrumentation and other payload systems of a solar rocket experiment are described in detail. The objectives of the rocket payload were: (1) to carry out high-spectral-resolution measurements of a coronal active region in the X-ray and extreme ultraviolet regions at the same time as high-spatial-resolution measurements were being made of the same active region by the Apollo Telescope Mount experiments flown on Skylab; and (2) to derive a physical model of the conditions in the...
Topics: NASA Technical Reports Server (NTRS), APOLLO TELESCOPE MOUNT, ROCKET-BORNE INSTRUMENTS, SOLAR...
The status of the payload bay and the needs of infrared, ultraviolet and space plasma experiments were discussed. Those measurements important in each area were reviewed. Issues of concern and how these environmental conditions might impact experiments were considered. Several common issues were revealed, and recommendations were made.
Topics: NASA Technical Reports Server (NTRS), ENVIRONMENTAL MONITORING, INFRARED INSTRUMENTS, SPACE...
NASA Network Resource and Training Site
by NASA Technical Reports Server (NTRS)
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The possibilities for the use of high spectral resolution analysis in the field of hydrology and water resources are examined. Critical gaps in scientific knowledge that must be filled before technology can be evaluated involve the spectral response of water, substances dissolved and suspended in water, and substances floating on water. The most complete mapping of oil slicks can be done in the ultraviolet region. A mean of measuring the ultraviolet reflection at the surface from satellite...
Topics: NASA Technical Reports Server (NTRS), HIGH RESOLUTION, HYDROLOGY, REFLECTANCE, SPECTRAL RESOLUTION,...
NASA Network Resource and Training Site
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I propose to continue providing observers with basic data for interpreting spectra from stars, novas, supernovas, clusters, and galaxies. These data will include allowed and forbidden line lists, both laboratory and computed, for the first five to ten ions of all atoms and for all relevant diatomic molecules. I will eventually expand to all ions of the first thirty elements to treat far UV and X-ray spectra, and for envelope opacities. I also include triatomic molecules provided by other...
Topics: NASA Technical Reports Server (NTRS), LINE SPECTRA, SPECTRUM ANALYSIS, STELLAR SPECTRA, ULTRAVIOLET...
The need to improve the accuracy of measurement of the absolute solar flux within the wavelength range 120 nm to 400 nm requires an extensive effort in contamination control and in tracking the instruments' stability. The techniques used in the solar ultraviolet irradiance monitor are described. These methods resulted in very high calibration stability as proved by preflight and postflight calibration. In-flight calibrating and the pointing accuracy provided by the shuttle attitude control...
Topics: NASA Technical Reports Server (NTRS), ATTITUDE CONTROL, OSS-1 PAYLOAD, PHOTOMETERS, SOLAR FLUX...
The electron-impact-induced emission spectrum of H2 has been measured in the extended wavelength region 175-530 mm at a spectral resolution of 1.7 mm (FWHM). The laboratory spectra are characterized by underlying H2 (a (sup 3) Sigma(sup +, sub g) to b (sup 3) Sigma(sup +, sub u) continuum emission. together with many strong lines assigned to the radiative decay of the gerade singlet states of H2, and to members of the H Balmer series resulting from dissociative excitation of H2.
Topics: NASA Technical Reports Server (NTRS), HYDROGEN, EXCITATION, ELECTRON IMPACT, ULTRAVIOLET SPECTRA,...
NASA Network Resource and Training Site
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This program conducts solar system research in support of NASA missions and of general astronomical interest. Investigations of the composition, physical characteristics, and changes in solar system bodies are conducted primarily utilizing facilities of McDonald Observatory, but also utilizing various space vehicles where appropriate. The first detection of 2 micrometer II2 emission from Jupiter's southern auroral zone was made. Previous detection of northern auroral emission from Jupiter's H2...
Topics: NASA Technical Reports Server (NTRS), ASTRONOMICAL SPECTROSCOPY, AURORAS, CHARON, HALLEY'S COMET,...
NASA Network Resource and Training Site
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Interstellar extinction curves over the region 3600-1100 A for 17 stars are presented. The observations were made by the two Wisconsin spectrometers onboard the OAO-2 with spectral resolutions of 10 A and 20 A. The extinction curves generally show a pronounced maximum at 2175 plus or minus 25 A, a broad minimum in the region 1800-1350 A, and finally a rapid rise to the far ultraviolet. Large extinction variations from star to star are found, especially in the far ultraviolet; however, with only...
Topics: NASA Technical Reports Server (NTRS), INTERSTELLAR EXTINCTION, OAO 2, STELLAR ATMOSPHERES,...
The Japan Meteorological Agency started the spectral observation of solar ultraviolet (UV) irradiance on 1 January 1990 at Tateno, Aerological Observatory in Tsukuba (35 deg N, 140 deg E). The observation has been carried out using the Brewer spectrophotometer for the wavelengths from 290 to 325 nm with a 0.5 nm interval every hour from 30 minutes before sunrise to 30 minutes after sunset throughout a year. Because of remarkable similarity within observed spectra, an observed spectrum can be...
Topics: NASA Technical Reports Server (NTRS), IRRADIANCE, OZONE DEPLETION, RADIATION HAZARDS, SOLAR...
Both IUE short and long wavelength exposures of the 56 Peg system are discussed. This mild barium star has an X-ray luminosity of 3 x 10 to the 31st power ergs/1, comparable to the rapidly rotating RS CVn binary systems, yet lies in a region of the HR diagram where stellar X-rays are generally not observed. This cool, bright giant is not a rapid rotator and the key to understanding its emission lies in the recent discovery of its white dwarf companion. Accretion onto the white dwarf of...
Topics: NASA Technical Reports Server (NTRS), ASTRONOMICAL SPECTROSCOPY, BINARY STARS, GIANT STARS, STELLAR...
NASA Network Resource and Training Site
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The work performed during the 12-month period of this contract involved: (1) further analysis of latitudinal variations in the Venusian NO nightglow intensity from PVOUVS data; (2) corrections made to the input data for the VTGCM model, relating specifically to a factor of three increase in the three-body recombination rate coefficient of N + O; (3) consideration of limits on the rate of reaction of N-atoms with CO2; (4) consideration of the Venusian equivalent of the terrestrial hot N-atom...
Topics: NASA Technical Reports Server (NTRS), PIONEER VENUS SPACECRAFT, DATA PROCESSING, LATITUDE...
NASA Network Resource and Training Site
by NASA Technical Reports Server (NTRS)
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The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph with unprecedented sensitivity that was installed into the Hubble Space Telescope (HST) in May 2009, during HST Servicing Mission 4 (STS-125). We present the design philosophy and summarize the key characteristics of the instrument that will be of interest to potential observers. For faint targets, with flux F(sub lambda) approximates 1.0 X 10(exp -14) ergs/s/cm2/Angstrom, COS can achieve comparable signal to noise...
Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, SPECTROGRAPHS, ULTRAVIOLET SPECTRA,...
Defense Technical Information Archive
by Defense Technical Information Center
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This issue of the DASIAC Reaction Rate Data presents summaries of recent progress in investigations supported by the Defense Nuclear Agency in portions of its Reaction Rate Program, plus summaries of related work submitted by other non-DNA-funded investigators.
Topics: DTIC Archive, GENERAL ELECTRIC CO SANTA BARBARA CALIF DASIAC, *IONS, *REACTION KINETICS,...
NASA Network Resource and Training Site
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The Extreme Ultraviolet Explorer (EUVE) will conduct a survey of the entire celestial sphere in the extreme ultraviolet (UV) spectrum, 100 to 1000 angstrom units. This survey will be accomplished using four grazing incidence telescopes mounted on a spinning spacecraft whose spin axis is along the Sun line. Data is taken only when the spacecraft is in the Earth's shadow. The EUVE will be placed in a near circular orbit by a Delta expendable launch vehicle. The design orbit is circular at an...
Topics: NASA Technical Reports Server (NTRS), DATA LINKS, DEEP SPACE NETWORK, DOWNLINKING, EXTREME...
The variations of the total solar irradiance is an important tool for studying the Sun, thanks to the development of very precise sensors such as the ACRIM instrument on board the Solar Maximum Mission. The largest variations of the total irradiance occur on time scales of a few days are caused by solar active regions, especially sunspots. Efforts were made to describe the active region effects on total and spectral irradiance.
Topics: NASA Technical Reports Server (NTRS), IRRADIANCE, LIMB DARKENING, SOLAR ACTIVITY EFFECTS, SOLAR...
NASA Network Resource and Training Site
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During Cycles 10, 12, and 13, we obtained STIS G230LB, G430L, and G750L spectra of 378 bright stars covering a wide range in abundance, effective temperature, and luminosity. This HST/STIS Next Generation Spectral Library was scheduled to reach its goal of 600 targets by the end of Cycle 13 when STIS came to an untimely end. Even at 2/3 complete, the library significantly improves the sampling of stellar atmosphere parameter space compared to most other spectral libraries by including the...
Topics: NASA Technical Reports Server (NTRS), HUBBLE SPACE TELESCOPE, ABUNDANCE, CALIBRATING, LIBRARIES,...
The IUE Ultraviolet Spectral Atlas of Selected Astronomical Objects (or 'the Atlas'), is based on the data that were available in the IUE archive in 1986, and is intended to be a quick reference for the ultraviolet spectra of many categories of astronomical objects. It shows reflected sunlight from the Moon, planets, and asteroids, and also shows emission from comets. Comprehensive compilations of UV spectra for main sequence, subgiant, giant, bright giant, and supergiant stars are published...
Topics: NASA Technical Reports Server (NTRS), HERTZSPRUNG-RUSSELL DIAGRAM, IUE, MAIN SEQUENCE STARS,...
This paper reports the performance of the Instrument Pointing System (IPS) that flew on the National Aeronautics and Space Administration (NASA) ASTRO-2 Spacelab mission aboard the Space Shuttle Endeavour in March 1995. The IPS provides a stabilizing platform for the ASTRO-2 instrument payload complement that consists of three main experiments (telescopes). The telescopes observe stellar targets in the universe within the ultraviolet portion of the electromagnetic spectrum that must be observed...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, GYROSCOPIC STABILITY, INSTRUMENT...
NASA Network Resource and Training Site
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Over the last decade significant advances in technology have made possible development of instruments with substantially improved efficiency in the UV spectral region. In the area of optical coatings and materials, the importance of recent developments in chemical vapor deposited (CVD) silicon carbide (SiC) mirrors, SiC films, and multilayer coatings in the context of ultraviolet instrumentation design are discussed. For example, the development of chemically vapor deposited (CVD) silicon...
Topics: NASA Technical Reports Server (NTRS), FLIGHT INSTRUMENTS, MIRRORS, REMOTE SENSING, SOHO MISSION,...
NASA Technical Documents
by Milligan, J. E.; Stecher, T. P
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Ultraviolet stellar spectra from rocket soundings, comparison of observed radiation flux with model stellar atmospheres and interstellar radiation
Topics: ASTROPHYSICS, ULTRAVIOLET SPECTRA, ULTRAVIOLET SPECTROSCOPY, INTERSTELLAR RADIATION, RADIATION...
The Composite Infrared Spectrometer (CIRS) on the Cassini spacecraft has obtained numerous spectra of Saturn at varying spectral and spatial resolutions since Saturn Orbit Insertion in 2001. Emission lines due to water vapor in Saturn's stratosphere were first detected using whole-disk observations from the Infrared Space Observatory [1] and subsequently confirmed by the Submillimeter Wave Astronomy Satellite [2], CIRS has detected water and the data permit the retrieval of the latitudinal...
Topics: NASA Technical Reports Server (NTRS), STRATOSPHERE RADIATION, SATURN RINGS, WATER VAPOR, INFRARED...
Since the Solar Maximum Mission (SMM) satellite was launched, a large database has been built up of experiments using the Ultraviolet Spectrometer and Polarimeter (UVSP) instrument. Access to this database can be gained through the SMM Vax 750 computer at Goddard Space Flight Center. One useful way to do this is with a program called USEARCH. This program allows one to make a listing of different types of UVSP experiments. It is evident that this program is useful to those who would wish to...
Topics: NASA Technical Reports Server (NTRS), COMPUTER TECHNIQUES, DATA RETRIEVAL, SEARCH PROFILES, SOLAR...
Defense Technical Information Archive
by Defense Technical Information Center
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This atlas provides solar spectra with high spectral resolution which will satisfy the needs of both solar physics and aeronomy for information on the solar spectrum in the wavelength range 1175 to 2100 Angstroms. The spectra may furthermore be useful for comparison with stellar UV spectra and with the red shifted spectra of quasars. Specific intensities as functions of wavelength are shown for two quiet regions between 1175 and 2100 Angstroms and for one active region between 1680 and 2100...
Topics: DTIC Archive, Moe,O Kjeldseth, NAVAL RESEARCH LAB WASHINGTON D C, *SOLAR SPECTRUM, *ULTRAVIOLET...
Progress is described for the following topics: rapid variations in the far ultraviolet spectrum of the cool Ap star 21 Com; elliptical Seyfert galaxies; variations of cool Ap stars with strong magnetic fields; and X-ray selected BL Lac Objects.
Topics: NASA Technical Reports Server (NTRS), ASTRONOMY, BALMER SERIES, MAGNETIC FIELDS, ULTRAVIOLET...
NASA Network Resource and Training Site
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The purpose was to obtain ultraviolet flux measurements of Uranus before and after the January 1986 flyby past Uranus by Voyager. These measurements were used to determine absolute flux distributions in the wavelength range 1950 to 3200 A. This wavelength range is an important region to observe since the model atmospheres for Uranus indicate that the albedo spectrum in this region can tightly constrain the height of the photochemical haze layer.
Topics: NASA Technical Reports Server (NTRS), ALBEDO, ATMOSPHERIC COMPOSITION, PHOTOCHEMICAL REACTIONS,...
The Hubble Space Telescope (HST) is a high-performance astronomical telescope system designed to operate in low-Earth orbit. It is approximately 43 feet long, with a diameter of 10 feet at the forward end and 14 feet at the aft end. Weight at launch was approximately 25,000 pounds. In principle, it is no different than the reflecting telescopes in ground-based astronomical observatories. Like ground-based telescopes, the HST was designed as a general-purpose instrument, capable of using a wide...
Topics: NASA Technical Reports Server (NTRS), HUBBLE SPACE TELESCOPE, EARTH ATMOSPHERE, EARTH SURFACE,...
An account is given of progress of work on absorption cross section measurements of ozone at 300 K, 228 K and 195 K in the wavelength region 185-240 nm. In this wavelength region, the penetration of solar radiation into the Earth's atmosphere is controlled by O2 and O3. The transmitted radiation is available to dissociate trace species such as halocarbons and nitrous oxide. We have recently measured absolute absorption cross sections of O3 in the wavelength region 240-350 nm (Freeman et al.,...
Topics: NASA Technical Reports Server (NTRS), ABSORPTION CROSS SECTIONS, ATMOSPHERIC COMPOSITION, OZONE,...
Data analysis for Fe III was completed in 2004. The new spectra give wavelengths and some energy levels for Fe III that are at least an order of magnitude more accurate than values in the literature. However, the data set is missing - because they are outside the wavelength range that we can study at Imperial College or with ancillary FT spectroscopy measurements at NIST - important transitions that would allow all energy levels to be determined with improved accuracy. We are assessing...
Topics: NASA Technical Reports Server (NTRS), IRON, ULTRAVIOLET SPECTRA, GAS PRESSURE, ENERGY LEVELS,...
Observations of temporal variations of the solar UV spectral irradiance over several days to a few weeks in the 160-400 nm wavelength range are presented. Larger 28-day variations and a second episode of 13-day variations occurred during the second year of measurements. The thirteen day periodicity is not a harmonic of the 28-day periodicity. The 13-day periodicity dominates certain episodes of solar activity while others are dominated by 28-day periods accompanied by a week 14-day harmonic....
Topics: NASA Technical Reports Server (NTRS), LINE SPECTRA, NIMBUS 7 SATELLITE, SOLAR ACTIVITY, SOLAR...
An ultraviolet spectrum of NGC 7027 was obtained with a rocket-borne telescope. The observed fluxes are given on an absolute basis and upper limits are given for the strongest predicted lines which were not observed. The extinction correction was made on the basis of the observed and calculated line ratios for the hydrogenic recombination line of He 2 at 1640A to H beta. The extinction is in agreement with ground based determinations. When corrected for extinction the C 4 resonance line at...
Topics: NASA Technical Reports Server (NTRS), PLANETARY NEBULAE, ROCKET-BORNE INSTRUMENTS, ULTRAVIOLET...
Goddard High Resolution Spectrograph (GHRS) observations have revealed the presence of broad wings in the transition-region lines of AU Mic and Capella. It has been proposed that these wings are signatures of microflares in the transition regions of these stars and that the solar analog for this phenomenon might be the 'transition region explosive events' discussed by Dere, Bartoe, & Brueckner. We have analyzed GHRS observations of Procyon (F5 IV-V) and HR 1099 (K1 IV + G5 IV) to search for...
Topics: NASA Technical Reports Server (NTRS), STAR FORMATION, CHROMOSPHERE, EMISSION SPECTRA, LINE SPECTRA,...
Substantial evidence suggests that a UV Spectrally Absorbing Material (UV-SAM) exists on Triton's surface. This evidence is found in the positive slope in Triton's spectrum from the UV to the near-IR, and the increasing contrast in Triton's light curve in the blue and UV. Although it is now widely-thought that UV-SAM's exist on Triton, little is known about their distribution and spectral properties. The goal of this NDAP Project is to determine the spatial distribution and geological context...
Topics: NASA Technical Reports Server (NTRS), ABSORBERS (MATERIALS), GEOMORPHOLOGY, SPECTRUM ANALYSIS,...
The project was to measure the optical constants of CO2 ice in the spectral regions of weak absorption. Many previous measurements had been made by others in the strong absorption bands, but the weak regions had been poorly measured or not measured at all. In these regions the emissivity of CO2 frost and CO2 clouds is quite sensitive to particle sizes and to the value of the absorption coefficient, so the new measurements will have applications to energy budget and remote sensing of the Martian...
Topics: NASA Technical Reports Server (NTRS), ABSORPTION SPECTRA, CARBON DIOXIDE, CRYSTALS, ICE, INFRARED...
An account is given of progress in work on (1) the determination of band oscillator strengths of the Schumann-Runge absorption bands of (16)O2 and (18)O2 from cross section measurements conducted at 79 K; (2) the determination of the absolute absorption cross section of the Schumann-Runge bands of (16)O(18)O from optical depth measurements performed on mixtures of (16)O2, (18)O2 and (16)O(18)O at 79K; and (3) the influence of Schumann-Runge linewing contributions on the determination of the...
Topics: NASA Technical Reports Server (NTRS), ABSORPTION CROSS SECTIONS, ATMOSPHERIC COMPOSITION, HERZBERG...
Two balloon flights reaching float altitudes of approximately 30 and 40 km respectively, were used to obtain scans of the ultraviolet and visible solar spectra. Both flights covered the UV (2800-3500A) at approximately 0.3A resolution and the visible at approximately 0.6A. Numerous scans were obtained during ascent and from float for both flights. All spectral scans obtained at float, from high sun to low sun, were calibrated in wavelength by using several standard solar spectra for line...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC COMPOSITION, LIGHT (VISIBLE RADIATION), LINE...
American Libraries
by New York Public Library; Behrens, William B
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Book digitized by Google from the library of Harvard University and uploaded to the Internet Archive by user tpb.
Topic: Ultraviolet spectra
Source: http://books.google.com/books?id=p8IMAAAAYAAJ&oe=UTF-8
Progress in the investigation of absolute transition probabilities (A-values or F values) for ultraviolet lines is reported. A radio frequency ion trap was used for measurement of transition probabilities for intersystem lines seen in astronomical spectra. The intersystem line at 2670 A in Al II, which is seen in pre-main sequence stars and symbiotic stars, was studied.
Topics: NASA Technical Reports Server (NTRS), IONS, LINE SPECTRA, RADIATIVE LIFETIME, TRANSITION...
Space-borne facilities, such as the Hubble Space Telescope, the recent ORFEUS-SPAS II Shuttle mission, and the soon-to-be launched Far Ultraviolet Spectroscopic Explorer, are providing data at ultraviolet wavelengths of unprecedented quality for spectroscopic studies of many astronomical environments. The first step in the analysis of these data involves the derivation of abundances. Obtaining accurate abundances is possible only when the correspondence between line strength and abundance is...
Topics: NASA Technical Reports Server (NTRS), SPACE MISSIONS, ASTROPHYSICS, ULTRAVIOLET RADIATION, FAR UV...
The conditions within astrophysical environments can be derived from observational data on atomic and molecular lines. For instance, the density and temperature of the gas are obtained from relative populations among energy levels. Information on populations comes about only when the correspondence between line strength and abundance is well determined. The conversion from line strength to abundance involves knowledge of meanlives and oscillator strengths. For many ultraviolet atomic...
Topics: NASA Technical Reports Server (NTRS), ASTROPHYSICS, ATOMS, ENERGY LEVELS, GRAVITATION, INTERSTELLAR...
Most interstellar species have a large fraction of their electronic transitions at far ultraviolet wavelengths. Observations at these wavelengths reveal spectra rich in absorption lines seen against the continuum of a background source, such as a hot star in our Galaxy, a supernova in a nearby galaxy, or even a bright nucleus in an active galaxy. Most of the observations continue to be made with space-borne instruments, but recent work includes measurements of extragalactic material at large...
Topics: NASA Technical Reports Server (NTRS), ATOMS, MOLECULES, DATA ACQUISITION, INTERSTELLAR MATTER,...
The principal scientific objective of the Solar and Terrestrial Atmospheres Spectrometer (STAS) project is the measurement of the absolute ultraviolet solar spectral irradiance with: (1) resolution of better than 15 mA, and (2) absolute irradiance uncertainty at the state of the art (less than or equal to 3%). High measurement accuracy coupled with high spectral resolution are necessary to identify the nature of the radiation, its variability, and to identify solar processes which may cause the...
Topics: NASA Technical Reports Server (NTRS), EQUIPMENT SPECIFICATIONS, IRRADIANCE, SOLAR RADIATION, SPACE...
A total of 14 8 hour I.U.E. observing sessions resulted in 39 spectra of 11 asteroids and 9 solar type stars as well as 57 spectra at various locations on the disk of Jupiter. The Jupiter observations include a total of 5 center to limb series of spectra at various latitudes and a North South series along the central meridian. In the range from 2000-3000 A, the planet shows a striking decrease in brightness at latitudes greater than about 30 degrees, and exhibits limb brightening at low...
Topics: NASA Technical Reports Server (NTRS), ASTEROIDS, ASTRONOMICAL PHOTOMETRY, IUE, JUPITER (PLANET),...